DC Cox wrote:
The transistors are small BC337 and BC327 transistors. For my coils, the primary current with 9 V excitation is in the tens of mA, so any transistor is enough. For coils with lower impedance primaries, heavier transistors may be needed, or MOSFETs. A more complicated buffer, with feedback to lower the impedance, may be used too. It's interesting to tune a coil with this system. You see immediately what is the effect of changing the coupling, the load capacitance (move your hand close to the terminal or the secondary coil), etc.Antonio: What is the part number for the transistor you used with the 555 circuit? Is this a pair of transistors or a single xsistor in a Darlington configuration? Dr. Resonance
Antonio Carlos M. de Queiroz _______________________________________________ Tesla mailing list Tesla@xxxxxxxxxxxxxx http://www.pupman.com/mailman/listinfo/tesla